Bank Tech Test

Practice tech test in Week 10 at Makers Academy.

Build a simple command line program where a bank customer can make deposits, make withdrawls, and print their bank statements. See tech test requirements and approach.

Getting Started

Run Bundle Install

Before you run the program, make sure your gems are up to date by running:

$ bundle install

Running the program

IRB

2.6.3 :001 > require './lib/bank.rb'
 => true 
2.6.3 :002 > bank = Bank.new
 => #<Bank:0x00007fa8752753d8 @account=#<UserAccount:0x00007fa8752753b0 @balance=0, @transactions=[]>> 
2.6.3 :003 > bank.make_deposit(1000)
 => "Deposit of $1000 was successful" 
2.6.3 :004 > bank.make_deposit(2000)
 => "Deposit of $2000 was successful" 
2.6.3 :005 > bank.make_withdrawl(500)
 => "Withdrawl of $500 was successful" 
2.6.3 :006 > bank.print_statement
date || credit || debit || balance
25/02/2020 || || 500.00 || 2500.00
25/02/2020 || 2000.00 || || 3000.00
25/02/2020 || 1000.00 || || 1000.00

Running the tests

To run tests for this program, run:

$ rspec

Built With

• Ruby
• Rspec (testing)

User Stories

As a bank customer,
So I can keep my money at the bank,
I would like to make deposits.

As a bank customer,
So I can spend my money,
I would like to make withdrawls.

As a bank customer,
So I can see how much money I have at the bank,
I would like to print my bank statement.

As a bank customer,
So I can see all of my transaction details,
I would like my bank statement to include the date of each transaction.

As a bank customer,
So I can see all of my transaction details,
I would like my bank statement to include the credit/debit amount of each transaction.

As a bank customer,
So I can see all of my transaction details,
I would like my bank statement to include the balance after each transaction.

Requirements

• You should be able to interact with your code via a REPL like IRB or the JavaScript console. (You don't need to implement a command line interface that takes input from STDIN.)
• Deposits, withdrawal.
• Account statement (date, amount, balance) printing.
• Data can be kept in memory (it doesn't need to be stored to a database or anything).

Acceptance criteria

Given a client makes a deposit of 1000 on 10-01-2012
And a deposit of 2000 on 13-01-2012
And a withdrawal of 500 on 14-01-2012
When she prints her bank statement
Then she would see

date || credit || debit || balance
14/01/2012 || || 500.00 || 2500.00
13/01/2012 || 2000.00 || || 3000.00
10/01/2012 || 1000.00 || || 1000.00

Approach

• After reviewing the requirements and acceptance criteria, I broke down both into User Stories.
• I used the User Stories to diagram/model the classes I wanted to use.
• I decided on a Bank class, User Account class, Transaction class, and Statement Printer module.
  • The Bank class is where the user interacts with the program.
  • The User Account class holds the account balance, stores a list of Transactions, and initiates a new Transaction when the user makes a deposit or withdrawl.
  • The Transaction class holds the details of a transaction (type, amount, balance, date)
  • The Statement Printer module takes the array of Transactions and formats them into a string output
  • I could extend the program to include a Transaction Log class
• As always, I used TDD throughout.